Deep in the Juruá River Basin, one of the Amazon’s most isolated corners, a strange call pierced the rainforest noise. It wasn’t a bird or insect—Albertina Pimentel Lima knew that much. She and Alexander Mônico followed the sound through dense underbrush. What they found stunned them: a thumbnail-sized frog gleaming with metallic limbs, streaked in copper and blue. It was unlike anything they had seen before.

During follow-up expeditions across the 2024 rainy season, the team gathered recordings, observed behaviors, and performed genetic sequencing. The evidence was clear. This frog, just 1.5 centimeters long, was new to science. They named it Ranitomeya aetherea, published in a joint paper between Brazilian and Czech researchers in PLOS ONE.

But it wasn’t alone.

Two new species of poison dart frogs have been discovered in the Brazilian Amazon.

Meet the Metallic Poison Frogs

Alongside R. aetherea, researchers uncovered a second dazzling species—Ranitomeya aquamarina. Its jet-black skin bursts with turquoise stripes, earning it the nickname “metallic poison frog.” Despite their vivid appearance, both frogs are no larger than a dime and live among the leaf axils of palm-like plants called *Phenakospermum guyannense*, where rainwater collects and tadpoles can grow safely in small pools Daily Galaxy reports.

What sets these frogs apart isn’t just their looks. R. aetherea males are typically solitary, calling out for mates with a burst of 16 to 35 chirping notes lasting just milliseconds. According to New Scientist, the females seem to lay only one egg at a time. Esteban Koch, part of the discovery team, speculates they may return to lay unfertilized eggs later—fuel for the growing tadpole.

R. aquamarina, by contrast, may exhibit monogamous behavior, a rarity among amphibians, frequently appearing in pairs Daily Galaxy notes.

Scientists identified the species using genetics, acoustic calls, and microscopic anatomy.

Not Just Rare—They’re in Danger

Both frogs were found in forest fragments only a few miles apart. The area’s remoteness—a plane ride followed by a 10-hour boat trip—has kept it largely unsampled. That isolation may have shielded these creatures from human eyes. But it hasn't protected them from human reach.

Between the 2023 and 2024 expeditions, researchers saw signs of deforestation closing in on the frogs’ fragile habitats New Scientist reports. While these frogs’ conservation statuses remain uncertain, their small geographic range and specific habitat needs make them particularly vulnerable.

Their brilliant colors also raise fears of exploitation. Brightly colored frogs are often targeted for the illegal pet trade. Poison dart frogs, as a group, are known for toxins so potent they can kill a human with a touch, according to Newsweek. Though the source of these toxins likely comes from insects in their diet, scientists still don’t know the full picture.

Photo: PLOS One / Koch et al., License: CC-BY 4.0

A Call to Protect the Unknown

These frogs represent more than scientific curiosity. They are a warning—and a reminder. “We are likely losing a significant portion of biodiversity before we even have the chance to discover it,” Alexander Mônico told BBC Wildlife.

The Juruá River Basin remains one of the most pristine stretches of rainforest on Earth. And yet, even here, deforestation pushes deeper. The discoveries of R. aetherea and R. aquamarina bring new urgency to conservation efforts in the region.

For now, the frogs remain hidden gems in a rainforest that is changing fast. Whether they survive long enough to be studied in full—or vanish before we understand their story—depends on what happens next.